Among the six players who went down with injury in the San Francisco 49ers’ late comeback win in the preseason opener against the Dallas Cowboys, two of Kyle Shanahan’s most crucial weapons — running back Matt Breida and tight end George Kittle — exited with shoulder injuries.

According to reports from Tom Pelissero and Ian Rapoport of the NFL Network, both avoided serious injury.

On his weekly teleconference, Shanahan said that both sustained shoulder separations.

With 3:18 to go in the first quarter, Breida went for a cut block on defensive tackle Antwaun Woods, and looked to jam his shoulder. He walked off the field under his own power, escorted by 49ers medical staff. His MRI showed no structural damage, and, the report said, he could practice soon without contact.

After missing a deep pass by Jimmy Garoppolo 40 yards up the seam — an overthrow — Kittle, landed on his shoulder, and was examined on the sideline with 5:45 to go in the first. About a minute and a half of game time later, he went into the locker room with his right arm pinned tightly to his side.

His tests revealed no tears or structural damage on his separated shoulder. Kittle missed just one game last year, and figures to be a major target this season, backed up by Garrett Celek.

Celek did not catch a pass in the opener, but third-string second-year tight end Cole Hikutini had one catch for 18 yards, and rookie Ross Dwelley had three grabs for 44 yards. Cole Wick was inactive after sustaining an injury last week.

Others injured on Thursday included defensive tackle Solomon Thomas (concussion), offensive tackle Garry Gilliam (concussion) and linebackers Malcolm Smith (hamstring) and Eli Harold (lower leg). Shanahan said all six should be available for Week 1 against the Minnesota Vikings.